Sarah Brown's commitment has been admirable. Here was a neglected, unfashionable cause: maternal mortality, the millennium development goal that looked like it was going to slip under the radar. Fifth in the list of eight targets pledged by the members of the UN as a commitment to reach by 2015, progress has always been slow and now it is lamentably off track.

But at the same time why, listening to the declarations of more money for healthcare staff and calls for more commitment to tackle the painful lottery which so many African women face in childbirth, does my heart sink?

I spent last week sitting in a crowded hot meeting room in a district town six hours north east of Kampala in Uganda. The subject under discussion was the priorities for the final phase of the pioneering Katine project funded by Barclays and Guardian and Observer readers. In my breakout group there were farmers and teachers from the remote rural sub-county of Katine sitting alongside the district's most powerful politician. The issue was how to use limited resources as effectively as possible. It showed me very starkly why childbirth falls to the bottom of the priority list almost every time.

Here is how it works. Eighty per cent of the disease burden of Africa can be tackled at household level: simple cheap interventions such as malaria bednets and better hygiene – organising households to build pit latrines, wash hands – lead to dramatic improvements. It is the cycle of malaria and diarrhoea that weakens the immune system and results in short lives. If you have a tight budget this is what you start with. In projects across Africa, governments and non-governmental organisations work on "sensitisation" as it is called – or what we would call public health education. They usually rely on volunteers at a village level – often not even literate – to walk from house to house talking about the importance of hygiene. To us, this seems basic but it wasn't in many households in this country a few generations back. And again and again, these projects have been proved to work.

Voluntary health workers can urge pregnant mothers to attend antenatal clinics, they can encourage them to have their babies in hospital rather than depend on untrained birth attendants, but they can't do much beyond that.

What doesn't get fixed is acute care; it is vastly more complicated and expensive to improve the formal healthcare system. In Katine for example, the clinic for the sub-county that cares for 29,000 people has no doctor; attempts to recruit over the last two years have repeatedly failed. No Ugandan doctor wants to work in the middle of nowhere in a clinic with no electricity or running water.

But even getting to that clinic (where there are at least midwives and a senior health officer) is a huge effort for outlying villages. What is so easy to forget, sitting in Europe, is the enormous scale of Africa and how much of it still lacks a basic road network. There is one paved road in Katine, everywhere else its meandering bumpy paths through the bush which are often near impassable for vehicles. A pregnant woman has a walk of several hours sometimes to get to an antenatal appointment; a woman in labour has to balance on the back of a bike. If a caesarean is needed, the local clinic can't help and that means another journey to the district town. By that time, tragically a labouring woman in difficulties could be dead.

But there is another set of obstacles and last week revealed that to me very sharply. One of the issues that emerged very clearly in our meetings was the position of women. The room was crowded with men and one brave woman, a farmer, stood up to raise her concerns at how again and again, women are relegated to the margins in decision-making. This impacts on maternal mortality. When family budgets are tight, the decision to spend a tiny sum on a bicycle taxi to get the mother to her antenatal appointment is usually taken by the men. Sometimes, shockingly, a mother's life is regarded as cheap. The status of women in this part of Uganda is very low; they are expected to defer to their husbands in all things, to curtsey on meeting a man, to always speak in a soft, low, childlike voice. If they speak up at meetings, their husband might beat them on their return home that evening, we were told last week.

How do you shift these deeply ingrained attitudes? It requires generations of behavioural change and a determination to educate girls, and support their chances of training to ensure financial independence.

So the shameful statistics on maternal mortality are a dreadful reflection of poverty combined with the dominance of men in every aspect of life in remote areas of rural Africa. It's welcome that global leaders put this issue on the agenda in New York, but let's not be under any illusion that this is an issue on which progress can be quick or simple. And that should redouble our effort to keep campaigning on this because the cost of a lost mother is terrifying. It's the waste of a life much needed by her children whose wellbeing – the state of their stomachs, their education – is so dependent on their single most important protector: their mother.